Studies on the constituents of asclepiadaceae plants. 43. Component of Marsdenia tomentosa Decne. Structure of tomentomin.

A new polyoxypregnane derivative, tomentomin (12β-O-cinnamoyl-20α-O-nicotinoyltomentogenin), was isolated from the leaf of Marsdenia tomentosa. Tomentomin is the first tomentogenin derivative with nicotinic acid in ester-linking to be isolated from Asclepiadaceae plants.